2001163656 has 16 divisors (see below), whose sum is σ = 5002909200. Its totient is φ = 667054544.

The previous prime is 2001163651. The next prime is 2001163667. The reversal of 2001163656 is 6563611002.

It is not an unprimeable number, because it can be changed into a prime (2001163651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41690886 + ... + 41690933.

It is an arithmetic number, because the mean of its divisors is an integer number (312681825).

Almost surely, 2^2001163656 is an apocalyptic number.

It is an amenable number.

2001163656 is an abundant number, since it is smaller than the sum of its proper divisors (3001745544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2001163656 is a wasteful number, since it uses less digits than its factorization.

2001163656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83381828 (or 83381824 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 2001163656 is about 44734.3677277326. The cubic root of 2001163656 is about 1260.1653549680.

Adding to 2001163656 its reverse (6563611002), we get a palindrome (8564774658).

The spelling of 2001163656 in words is "two billion, one million, one hundred sixty-three thousand, six hundred fifty-six".